Electronic manifest of underground facility locate marks

ABSTRACT

A method performed by a device may include receiving information regarding a particular geographic area; retrieving an aerial image of the particular geographic area; displaying the aerial image; determining an approximate geographic location of a mark denoting an underground facility; overlaying, on the displayed aerial image, information concerning the approximate geographic location of the mark denoting the underground facility; and storing the aerial image and the information concerning the approximate geographic location of the mark denoting the underground facility.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims a priority benefit, under 35 U.S.C. §120, as acontinuation (CON) of U.S. Non-provisional application Ser. No.12/029,732, entitled “ELECTRONIC MANIFEST OF UNDERGROUND FACILITY LOCATEMARKS,” filed on Feb. 12, 2008 under attorney docket no. DYC0003US00.The above-identified application is hereby incorporated herein byreference in its entirety.

BACKGROUND

Excavators are required to notify underground facility owners/operatorsin advance of their excavation activities and to describe andcommunicate the geographic area of those activities to undergroundfacility owners/operators. The geographic area so described is commonlyreferred to as “the dig area.” In turn, facility owners/operators arerequired to determine if they own or operate any underground facilitiesat an identified dig area. The presence of underground facilities at adig area is generally detected using a device commonly referred to as a“locate wand.” Locate wands use a number of electronic methods to detectthe presence of underground facilities. The location of thoseunderground facilities, if any, which exist within a dig area, is markedusing paint or some other physical marking system, such as flags. Paintis generally applied as a sequence of dashes or dots on the surface(grass, dirt, asphalt, concrete, etc.) directly above the undergroundfacility and is color-coded to indicate to the excavator the type (e.g.,gas, water, sewer, power, telephone, cable television, etc.) of theunderground facility present. Flags, which also may identify theunderground facility via color-coding, can be placed in the grounddirectly above the underground facility being marked. Paint and/or flagscan be dispensed using various devices. The application of paint, flags,or some other marking object to indicate the presence of an undergroundfacility is called a “locate.” The marks resulting from a locate arecommonly called underground facility “locate marks.”

Underground facility owners/operators may perform locates with in-houseemployees or choose to hire independent contract locating firms toperform locates on their behalf. Generally, the person performing thelocate operation is called a locate technician. The set of instructionsnecessary for a locate technician to perform a locate operation may becalled a “ticket.” A ticket might specify, for example, the address ordescription of the dig area to be marked, the day and/or time that thedig area is to be marked, and/or whether the user is to mark the digarea for telecommunications (e.g., telephone and/or cable television),power, gas, water, sewer, or some other underground facility.

It is generally recommended, or in some jurisdictions required, todocument the type and number of underground facilities located, i.e.telephone, power, gas, water, sewer, etc., and the approximategeographic location of the locate marks. Often times it is alsorecommended or required to document the distance, or “offset” of thelocate marks from environmental landmarks that exist at the dig area. Anenvironmental landmark may include any physical object that is likely toremain in a fixed location for an extended period of time. Examples ofan environmental landmark may include a tree, a curb, a driveway, autility pole, a fire hydrant, a storm drain, a pedestal, a water meterbox, a manhole lid, a building structure (e.g., a residential or officebuilding), or a light post. For example, a telephone cable located twoand a half meters behind the curb of a residential street would bedocumented as being offset two and a half meters behind the curb. Theseoffsets serve as evidence supporting the location of the locate marksafter those locate marks may have been disturbed by the excavationprocess.

Documentation of some or all of the information regarding a locateoperation is often called a “manifest.” A manifest may typically containa variety of information related to a locate operation including asketch or drawing of the dig area that identifies the approximatelocation of the locate marks and environmental landmarks present at thedig area; the time and date the locate operation was performed;identification of the entity and the locate technician performing thelocate operation; the entity requesting the locate operation; thegeographic address of the dig area; the type of markings used for thelocate operation (e.g., colored paint, flags, or other markers); notesfrom the locate technician; and/or a technician signature.

If performing locate operations with in-house employees, each individualunderground facility owner/operator generally documents on the manifestonly the existence of its facilities and the approximate location of itslocate marks. If an independent contract locating firm is hired toperform locates for more than one underground facility owner/operator,the contract locating firm may document on the manifest some or all ofthe underground facilities at the dig area that it located and theapproximate location of all the locate marks.

Currently, locate marks are generally documented using a sketchingprocess which results in the creation of a paper manifest. Sketches areproduced by hand, are not to scale, prone to human error, and costly indrafting time spent by the locate technician. They are stored manuallyor in some jurisdictions are digitally scanned/photographed and theimage stored electronically. Because the manifests are stored as paperor digital images, they are not easily interrogated for data in anymechanized way.

SUMMARY

According to one aspect, a method performed by a device may includereceiving information regarding a particular geographic area; retrievingan aerial image of the particular geographic area; displaying the aerialimage; determining an approximate geographic location of a locate markdenoting an underground facility; overlaying, on the displayed aerialimage, information concerning the geographic location of the locate markdenoting the underground facility; and storing the aerial image and theinformation concerning the approximate geographic location of the locatemark denoting the underground facility.

According to another aspect, a device may include a memory to storeaerial images of a plurality of geographic areas and a processing unit.The processing unit may receive information regarding a particular oneof the geographic areas; retrieve one of the aerial images from thememory based on the received information; receive information concerningan approximate geographic location of an underground facility locatedwithin the particular geographic area; present, on the retrieved aerialimage, information concerning the approximate geographic location of theunderground facility locate marks; and store the retrieved aerial imageand the information concerning the approximate geographic location ofthe underground facility locate mark.

According to a further aspect, a system may include means foridentifying a geographic area; means for retrieving an aerial image ofthe geographic area; means for displaying the retrieved image; means forreceiving input from a user concerning an approximate geographiclocation of underground facility locate marks that are located withinthe geographic area; means for presenting, on the displayed aerialimage, a marking that identifies the approximate geographic location ofthe underground facility locate marks within the geographic area; andmeans for storing the displayed aerial image with the marking thatidentifies the approximate geographic location of the undergroundfacility locate marks.

According to another aspect, a system may include a central server tostore a plurality of aerial images of a corresponding plurality ofgeographical locations; and a user device. The user device may identifya particular geographic location; determine whether the user devicestores an aerial image corresponding to the particular geographiclocation; retrieve the aerial image from the central server when theuser device does not store the aerial image corresponding to theparticular geographic location; retrieve the aerial image from a localmemory when the user device stores the aerial image corresponding to theparticular geographic location; display the aerial image; receiveinformation regarding an approximate location of underground facilitylocate marks located at the particular geographic location; and present,on the displayed aerial image, a marking that identifies the approximatelocation of the underground facility locate marks.

According to still another aspect, a method performed by a device mayinclude receiving information regarding a particular geographic area;retrieving an aerial image of the particular geographic area; receiving,from a GPS-enabled device, information regarding an approximate locationof underground facility locate marks; displaying, as a combined image,the aerial image and the information regarding the approximate locationof underground facility locate marks; and storing the combined image.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate one or more embodiments describedherein and, together with the description, explain these embodiments. Inthe drawings:

FIG. 1 is a diagram of a concept described herein;

FIG. 2 is a diagram of an exemplary network in which systems and methodsdescribed herein may be implemented;

FIG. 3 is a diagram of exemplary components of the user device of FIG.2;

FIG. 4 is a diagram of exemplary components of the central server ofFIG. 2;

FIG. 5 is a diagram of exemplary software routines for components ofFIG. 2;

FIG. 6 is a flowchart of an exemplary process for creating an electronicmanifest of underground facility locate marks;

FIG. 7 is a diagram of an exemplary data set that may be stored in thememory of FIG. 3 and/or FIG. 4; and

FIG. 8 is a diagram of an exemplary user interface that may be presentedvia the user device of FIG. 2.

DETAILED DESCRIPTION

The following detailed description refers to the accompanying drawings.The same reference numbers in different drawings may identify the sameor similar elements. Also, the following detailed description does notlimit the invention.

Overview

FIG. 1 is a diagram of a concept described herein. When locatingunderground facilities at a geographic location, such as at a dig area100 associated with a residence or a business, it may be beneficial todocument locate marks in a permanent and reproducible manner. Forexample, a locate technician may locate and mark underground facilitiesusing a locating device and/or a marking device. A locating device maygenerally be defined as a locating wand or another device used to detectthe presence of underground facilities; while a marking device maygenerally be defined as any tool to apply paint or other material to asurface, such as a paint wand. The locate technician may use paint,flags, or some other object with a particular color or othercharacteristic to mark the location of an underground facility.Referring to the example shown in FIG. 1, the locate technician may usered paint to mark underground power lines 110, orange paint to marktelecommunications (e.g., telephone and/or cable television) lines 120,and yellow paint to mark gas lines 130.

The locate technician may also identify one or more environmentallandmarks that are present at or near the dig area and/or determine thedistance between the environmental landmark(s) and the locatedunderground facility. For example, a transformer 140 may be indicated asan environmental landmark, as shown in FIG. 1. The geographic locationof transformer 140 may be used to measure offsets to other locate marksin the dig area.

As described herein, documentation of some or all of this informationregarding a locate operation is created as an electronic manifest. Anelectronic manifest, as used herein, may generally refer to one or morecomputer-readable files that include some or all of the information in amanifest. The electronic manifest may be created using aerial images ofa dig area, such as dig area 100, that may be combined with informationthat is added by the user about the locate marks and/or theenvironmental landmarks. In other implementations, an electronicmanifest may be created using aerial images of a dig area combined withinformation about locate marks that is provided by other sources. Otherimplementations may use aerial images of a dig area combined withinformation that is added by the user and information that is providedby other sources. As used herein, an “aerial image” is intended to bebroadly interpreted as any image taken from above the earth's surface,such as, for example, images generated using a satellite, airplane,helicopter, or other moving or fixed device. Also as used herein, a“user” may refer to any person operating a device to create anelectronic manifest, such as a locate technician, a site supervisor, orany other person or group of people.

Exemplary Network

FIG. 2 is a diagram of an exemplary network 200 in which systems andmethods described herein may be implemented. As shown in FIG. 2, thenetwork 200 may include a user device 210 connected to a central server220 and an image server 230 via a network 240. A single user device 210,central server 220, and image server 230 have been illustrated asconnected to network 240 for simplicity. In practice, there may be moreor fewer user devices and/or servers. For example, in one alternativeimplementation, the user device 210 may operate as a comprehensivedevice and, thus, the network 200 may include no central server, withuser device 210 communicating directly through network 240 to imageserver 230. Also, in some instances, the user device 210 may perform oneor more of the functions of the central server 220 and/or central server220 may perform one or more of the functions of the user device 210. Instill another implementation, multiple user devices 210 may be connectedto the central server 220 through the network 240.

The user device 210 may encompass a computer device, such as a laptopcomputer, a small personal computer, a tablet device, a personal digitalassistant (PDA), a mobile computing device, a touch-screen device, orgenerally any device including or connecting to a processor and adisplay. The user device 210 may be portable so as to be separatelycarried by the user performing a locate operation. Alternatively, theuser device 210 may be integrated with or affixed to another moveableobject, such as a vehicle.

The central server 220 may include a computer device that may storeinformation received from or provided to the user device 210 and/or theimage server 230. The central server 220 may include storage capacityand/or optionally include networked access to one or more separatehardware components, such as images cache 235, to store cached imagesand the like.

The image server 230 may include a computer device that may store andprovide aerial images of geographic locations The image server 230 maybe associated with the same, or a different, party that maintains thecentral server 220. For example, the image server 230 may be associatedwith a party that provides aerial images for a fee.

The network 240 may include a local area network (LAN), a wide areanetwork (WAN), a telephone network, such as the Public SwitchedTelephone Network (PSTN) or a cellular network, an intranet, theInternet, a communications link, or a combination of networks. The userdevice 210, central server 220, and image server 230 may connect to thenetwork 240 via wired and/or wireless connections. The user device 210and central server 220 may communicate using any communication protocol.

Exemplary User Device Architecture

FIG. 3 is a diagram of exemplary components of the user device 210. Theuser device 210 may include a bus 310, a processing unit 320, a memory330, an input device 340, an output device 350, a locationidentification unit 360, and a communication interface 370. In anotherimplementation, the user device 210 may include more, fewer, ordifferent components. For example, the location identification unit 360may not be included, or the location identification unit 360 may beincluded as a device located external to the user device 210, such as adevice worn or carried by a user of the user device 210.

The bus 310 may include a path that permits communication among thecomponents of the user device 210. The processing unit 320 may include aprocessor, a microprocessor, or processing logic that may interpret andexecute instructions. The memory 330 may include a random access memory(RAM), a read only memory (ROM), a memory card, a magnetic and/oroptical recording medium and its corresponding drive, or another type ofmemory device. Generally, the memory 330 may be sufficient to store andmanipulate aerial images, such as those stored in a local image cache335. In one implementation, the local image cache 335 may include one ormore aerial images of a dig area to be marked by a user. In anotherimplementation, the local image cache 335 may include a series of aerialimages that correspond to the geographical region to which a particularuser is assigned. For example, local image cache 335 may include acollection of high-resolution images of a particular zip code or town.In still another implementation, the local image cache 335 may includean entire set of aerial images intended to be made available to multipleusers.

The input device 340 may include one or more mechanisms that permit auser to input information to the user device 210, such as a keyboard, akeypad, a touchpad, a mouse, a stylus, a touch screen, a camera, or thelike. Alternatively, or additionally, the input device 340 may include amicrophone that can capture a user's intent by capturing the user'saudible commands. Alternatively, or additionally, the input device 340may interact with a device that monitors a condition of the user, suchas eye movement, brain activity, or heart rate. The output device 350may include a mechanism that outputs information to the user, such as adisplay, a speaker, or the like.

The location identification unit 360 may include a device that candetermine its geographic location to a certain degree of accuracy, suchas a global positioning system (GPS) or a global navigation satellitesystem (GNSS) receiver. In another implementation, the locationidentification unit 360 may include a device that determines locationusing another technique, such as tower (e.g., cellular tower)triangularization. The location identification unit 360 may receivelocation tracking signals (e.g., GPS signals) and determine its locationbased on these signals. In one implementation, location identificationunit 360 may be capable of determining its location within approximatelythirty centimeters or less.

The communication interface 370 may include any transceiver-likemechanism that enables user device 210 to communicate with other devicesand/or systems. For example, the communication interface 370 may includemechanisms for communicating with another device or system via anetwork. For example, the communication interface 370 may enablecommunications between the user device 210 and the central server 220and/or image server 230 over network 240.

As will be described in detail below, user device 210 may performcertain operations relating to the documentation of locate operationsand/or the creation of an electronic manifest. User device 210 mayperform these operations in response to the processing unit 320executing software instructions contained in a computer-readable medium,such as the memory 330. A computer-readable medium may be defined as aphysical or logical memory device.

The software instructions may be read into the memory 330 from anothercomputer-readable medium, or from another device via the communicationinterface 370. The software instructions contained in the memory 330 maycause processing unit 320 to perform processes that will be describedlater. Alternatively, hardwired circuitry may be used in place of, or incombination with, software instructions to implement processes describedherein. Thus, implementations described herein are not limited to anyspecific combination of hardware circuitry and software.

Exemplary Central Server Architecture

FIG. 4 is a diagram of exemplary components of the central server 220.The central server 220 may include a bus 410, a processing unit 420, amemory 430, and a communication interface 440. In anotherimplementation, the central server 220 may include more, fewer, ordifferent components. For example, an input device and/or an outputdevice (not shown) may be included, as necessary.

The bus 410 may include a path that permits communication among thecomponents of the central server 220. The processing unit 420 mayinclude a processor, a microprocessor, or processing logic that mayinterpret and execute instructions. The memory 430 may include amagnetic and/or optical recording medium and its corresponding drive, aRAM, a ROM, a memory card, or another type of memory device suitable forhigh capacity data storage. Generally, the memory 430 may be sufficientto store aerial images of particular geographic locations, such as thosestored in a central image cache 435. In one implementation, the centralimage cache 435 may include a set of aerial images that correspond tothe geographical regions to which a group of users are assigned. Instill another implementation, the central image cache 435 may includethe entire set of aerial images intended to be made available to any ofa group of users. For example, central image cache 435 may include acollection of high-resolution aerial images of a particular county,state or other geographic region. In another implementation, as shown inFIG. 2, central image cache 435 may be replaced or supplemented with oneor more networked storage components, such as image cache 235.

The communication interface 440 may include any transceiver-likemechanism that enables the central server 220 to communicate with otherdevices and/or systems. For example, the communication interface 440 mayinclude mechanisms for communicating with another device or system via anetwork. For example, the communication interface 440 may enablecommunications between the central server 220 and the user device 210and/or image server 230 over network 240.

As will be described in detail below, the central server 220 may performcertain operations to facilitate the documentation of locate operationsand/or the creation of an electronic manifest. The central server 220may perform these operations in response to the processing unit 420executing software instructions contained in a computer-readable medium,such as the memory 430.

The software instructions may be read into the memory 430 from anothercomputer-readable medium, or from another device via the communicationinterface 440. The software instructions contained in the memory 430 maycause processing unit 420 to perform processes that will be describedlater. Alternatively, hardwired circuitry may be used in place of or incombination with software instructions to implement processes describedherein. Thus, implementations described herein are not limited to anyspecific combination of hardware circuitry and software.

Exemplary Routines

FIG. 5 is a diagram of exemplary software routines for the componentsshown in FIG. 2. The central server 220 may include an image retrievalroutine 510 and a central image cache routine 520. The user device 210may include a synchronize routine 530, a local image cache routine 540,an image display routine 550, a user input routine 560, and a ticketmanager routine 570. As discussed in more detail herein, the examples ofroutines associated with the central server 220 and the user device 210may be interchangeable between each hardware component. Furthermore,some or all of routines 510, 520, 530, 540, 550, 560, and 570 need notbe performed exclusively by any one hardware component.

Still referring to FIG. 5, the image server 230 may store a library ofaerial images. Generally, the aerial images may be of sufficientresolution at an optimal elevation to be useful as a record of thelocate operation. The aerial images from the image server 230 mayinclude geocoding or other geographical identification metadata and maybe provided in any computer-readable format, such as JPEG fileinterchange format (JPEG), tagged image file format (TIFF), portabledocument format (PDF), graphics interchange format (GIF), bitmap (BMP),portable network graphics (PNG), Windows® metafile (WMF), and/or thelike. Also, aerial images from the image server 230 may include acombination of images or overlays, such as overlays of street names,regions, landmark descriptions, and/or other information about areasdisplayed in an image. The aerial images from the image server 230 maybe supplied by a third-party provider if the coverage area of thethird-party image provider overlaps with the desired area of the user.

The central image cache routine 510 and the image retrieval routine 520of the central server 220 may include a variety of functionalities. Incertain implementations, the central image cache routine 510 may receiveinformation about specific tickets and parse tickets in order to discernlocation information. For example, a ticket may identify the dig area byan address of the property or by geographic coordinates. The ticketmight specify, for example, the address or description of the dig areato be marked, the day and/or time that the dig area is to be marked,and/or whether the user is to mark the dig area for telecommunications(e.g., telephone and/or cable television), power, gas, water, sewer, orsome other underground facility.

The central image cache routine 510 may also convert dig area locationinformation to latitude/longitude coordinates or other coordinates. Whenlocation information from a ticket is sufficiently precise to allow foridentification of corresponding imagery, the central image cache routine510 may calculate the image extent (which may be generally defined asthe bounding region of the dig area of interest), and update the ticketwith the calculated extent. In one implementation, the central imagecache routine 510 may determine image date, coordinates, and resolutionof each image that may be stored in the central image cache 435 or inanother location. In another implementation, when location informationfrom a ticket is imprecise (or “fuzzy”), the central image cache routine510 may mark the ticket to indicate that no corresponding image was ableto be retrieved based on the ticket information.

In another implementation, central image cache 510 may identify an imageto retrieve based on GPS coordinates of a GPS-enabled device associatedwith a user. For example, a user may arrive at an excavation site in aGPS-enabled vehicle and the GPS information from the vehicle may be usedto identify coordinates corresponding to an image to be retrieved. GPScoordinates may also be obtained from other GPS-enabled devices beingused by or in the vicinity of the user. As used herein a GPS-enableddevice may include any device or combination of devices capable ofinterfacing with a global navigation satellite system, geo-spatialpositioning system, or other location-identification system to determinea location. Examples of GPS-enabled devices may include a marking device(e.g., a paint wand) with an integrated GPS receiver; a locating device(e.g., a locating wand) with a GPS receiver; a wearable GPS-enableddevice; a vehicle-mounted GPS system; certain PDAs, computers, andcellular telephones; and stand-alone GPS-enabled systems.

In still another implementation, central image cache 510 may identifyone or more images to request based on a designated geographical areaassigned to a user. For example, a user may be assigned to work inseveral dig areas associated with a particular section of aneighborhood. The user may input coordinates associated with the entireselected section of the neighborhood, and central image cache 510 maythen retrieve images for those coordinates.

The image retrieval routine 520 catalogues and stores images from theimage server 230 to the central server 220. For example, images may bestored in the central image cache 435 in the memory 430 of the centralserver 220. In one implementation, the image retrieval routine 520 mayquery the central image cache 435 or other cache for an image associatedwith a particular dig area relating to a ticket of interest, anddetermine, based on (for example) the age and resolution of the cachedimage, whether the image in the central image cache 435 needs to beupdated from the image server 230.

In another implementation, the image retrieval routine 520 may interfacewith multiple image providers and image servers 230. The image retrievalroutine 520 may determine which image provider is the best source forthe image corresponding to a particular dig area relating to a ticket ofinterest based on algorithms that factor, for example, each imageprovider's geographical coverage, image resolution, cost, andavailability. Regarding geographical coverage, it will be beneficial toconfirm that the image provider's area of coverage includes the desiredextent (in other words, the entire geographical region of interest tothe user).

Regarding image resolution, available resolution may be measured inmeters (or centimeters, feet, or inches) per pixel. For example, oneprovider may offer thirty centimeters per pixel, while another offersfifteen centimeters or less per pixel, for the same coverage area. If animage is requested at a standard altitude, then the image retrievalroutine 520 may choose a pre-defined optimal scale (for example, thirtycentimeters per pixel for a rural area, but fifteen centimeters perpixel for an urban area) and determine which provider provides images atthe pre-defined optimal scale. Alternatively, if the image of interestis at a less granular scale (for example, a community or neighborhoodimage that allows the locator to pan around the image), then resolutionmay not be a significant factor.

Regarding cost, the image retrieval routine 520 may have access topricing information for a variety of image providers. The imageretrieval routine 520 may identify which provider has the lowest costfor the desired image. Cost analysis may be based on images desired foran individual ticket or the algorithm may account for a group of imagerequests, including volume incentives and/or penalties from each imageprovider

Regarding availability of image providers, the image retrieval routine520 may identify what providers are available and/or operational. Also,if an image provider has a regular latency profile (for example, if aprovider has a particular server that is busiest 3-5 PM Pacific time),then the image retrieval routine 520 may manage requests to be providedto another image provider or to a particular server of that imageprovider to efficiently load share the image retrieval.

When an image provider is selected, the image retrieval routine 520 maydownload the image from the selected image provider's server, which maybe an image server 230. The downloaded image may be stored locally, forexample, in the central image cache 435.

It should be understood that some of the routines and/or functionalitiesdescribed above with respect to the central image cache routine 510 andthe image retrieval routine 520 may be performed by one or both of theroutines 510 and 520 above, and the arrangement of functionalities arenot limited to the implementations disclosed herein.

The synchronize routine 530 for user device 210 may ensure that imagesalready stored and manipulated on the user device 210 correspond toimages stored in the central server 220. When a user performing a locateoperation identifies a ticket or dig area, the synchronize routine 530may check if an image exists in the central server 220 that matches theextent requested, and if the matching image is up-to-date in, forexample, the local image cache 335. The synchronize routine 530 may alsosynchronize images from the central server 220 cache and store copieslocally in the user device 210.

If the ticket has a valid extent (i.e., a recognizable boundary), thelocal image cache routine 540 may associate the ticket information withan image matching the extent. The local image cache routine 540 may loadthe image from the local image cache 335. If the ticket does not have avalid extent, the local image cache routine 540 may accept addressinformation that is entered by the user. Alternatively, the local imagecache routine 540 may read the local address information from the ticketor from a GPS-enabled device in communication with the user device 210so that address information may be pre-entered for the user to theextent possible. Address information may include, for example, a streetaddress, street name, city, state and/or zip code. If either none ormultiple stored addresses appear to be associated with particularaddress information, the local image cache routine 540 may display alist of best match addresses from which a user can select.

Once an image is loaded from the local cache 335, image display routine550 may provide a variety of view options for the user. For example, theimage display routine 550 may support zooming in and out of the image bychanging the image scale. Also, the image display routine 550 maysupport panning horizontally and vertically in the image. Furthermore,the image display routine 550 may support “roaming” outside theboundaries of the initial extent. Roaming generally occurs when the userzooms or pans, such that images beyond the boundaries of the storedimages may be required to be retrieved (using, for example, synchronizeroutine 530) from either the local image cache 335 or the central server220. The additional images retrieved from either the local image cache335 or the central server 220 may be displayed and stitched together todisplay a complete image.

The user input routine 560 allows the user to add information to theimage to create an electronic manifest. The user input routine 560 mayaccept user input from, for example, input device 340, and may supportthe addition of lines, freehand forms (or scribbling), shapes such ascircles and rectangles, shading, or other markings which denote theapproximate location of underground facilities which are present withinthe dig area. A drawing shape may generally be any kind of drawing shapeor mark. The user input routine 560 may further enable drawing ofunderground facility locate marks for telecommunications (e.g.,telephone and cable television), gas, power, water, sewer, and the like,so that each type of drawn locate mark is distinguishable from theother(s). The user input routine 560 may limit the display of suchfacilities by the type of work which is to be performed according to theinstructions included within the user's assigned ticket. In addition tothe marking of the underground facility locate marks on the aerialimage, user input routine 560 may also include offsets fromenvironmental landmarks that may be displayed on the image in, forexample, English or metric units. Environmental landmarks may also bemarked and/or highlighted on the aerial image. The user input routine560 may also accept positioning information from external sources, suchas a GPS-enabled device. The user input routine 560 may further includefeatures to annotate the image with text and to revise user inputs by,for example deleting, dragging or pasting shapes. In one implementation,when the user zooms the image view in or out, user input (e.g., linesand/or shapes) that have been added to the original image may adhere tothe changing image scale and remain in the original user-inputlocations.

The electronic manifest, which is a compilation of the aerial image anduser inputs, may be saved as an image file. In another implementation,the user inputs may be saved in a mark-up format, including thegeo-coordinates and underground facility type of each input.

In one implementation, the user device 210 may interface with a ticketmanagement program for coordinating multiple tickets. The ticket managerroutine 570 may facilitate such an interface. The ticket managementprogram for coordinating multiple tickets may reside on the centralserver 220, for example, or on a separate server that is accessible tothe user device 210. Generally, tickets may be stored on a centralserver and assigned to a user. When a user edits a ticket, the user mayalso have created an electronic manifest associated with the ticket. Theticket manager routine 570 may allow the user to synchronize the user'sticket cache with the company's central database and also synchronizethe images and user input. The ticket manager routine 570 may copyimages from the central server 220 to the user device 210 for newtickets, and will copy the user input from the user device 210 to thecentral server 220 for completed tickets. The ticket manager routine 570may interface with the routines described above to correlate a user'sassigned tickets with images for those tickets and download the imagesto the user device from the central server 220. The ticket managerroutine 570 may retrieve the corresponding ticket number from the ticketmanagement program when the user retrieves an image, or the ticketmanager routine 570 may retrieve the image corresponding to an enteredticket number.

FIG. 6 provides a flowchart 600 of an exemplary process for creating anelectronic manifest relating to underground facility locate marks. Inone implementation, at least some of the blocks of FIG. 6 may beperformed using user device 210 (FIG. 2). In another implementation, oneor more of the blocks of FIG. 6 may be manually performed or performedby another device, such as central server 220.

The process 600 may begin with a user being dispatched to a dig area tobe located. The user might be given a ticket that identifies whatunderground facilities the user needs to locate at the dig area. Theticket might specify, for example, the address or description of the digarea to be located, the day and/or time that the dig area is to belocated, and/or whether the user is to locate the dig area fortelecommunications, power, gas, water, sewer, or other undergroundfacility. Based on information in the ticket, or other information aboutthe dig area to be located, user device 210 in block 610 may associatethe property address with a stored aerial image of the dig area. Suchassociation may include associating the address with geographic locationinformation, such as global positioning coordinates for the dig areaextent (or boundary).

In block 620, the stored aerial image associated with the dig area to belocated is retrieved from a cache of images and loaded into the userdevice 210. As previously described discussed herein with respect toFIG. 5, the cache of images may reside within the user device 210, thecentral server 220, a separate image server, or another storage device.

In block 630, the user may perform a locate operation to locate theunderground facilities present within the dig area and mark the locatedunderground facilities using a locating device and/or marking device, ora combined locating/marking device. For example, the user may use thelocating device to identify an underground facility at the dig area, andmay use the marking device to mark the underground facility with theappropriate marker (e.g., color paint, flag, or some other object). Incertain implementations, information regarding the approximategeographic location of the applied underground facility locate marks maybe gathered and stored electronically using a GPS-enabled device orother location identification device. The approximate geographiclocation of the underground facility locate marks may be determined, forexample, by identifying the current geographic location of theGPS-enabled device as the user performs the locating or marking. Inanother implementation, a user may use a triangularization technique todetermine the approximate geographic location of the undergroundfacility locate marks. In yet another implementation, a user maydetermine latitude and longitude coordinates or some other measurementof a geographic location.

In block 640, information about the approximate geographic location ofthe underground facility locate marks may be added to the stored aerialimage that was retrieved previously in block 620. The information aboutthe approximate geographic location of the underground facility locatemarks may be input by the user using an input device, such as inputdevice 340 (FIG. 3) of user device 210. Additional aspects regardinginformation to be input by the user is discussed in more detail hereinwith respect to FIG. 8.

Still referring to block 640, information about the approximategeographic location of the underground facility locate marks may also bereceived directly from a GPS-enabled device, such as the GPS-enabledlocating device or marking device used in block 630, and overlaid on theretrieved image. The user may use of a combination of received GPSinformation and manual entries to create an electronic manifest of theunderground facility locate marks.

In block 645, if necessary, information about offsets of the undergroundfacility locate marks from environmental landmarks may be added to thestored aerial image that was retrieved previously in block 620. As withthe input of the facility locations in block 640, the location of theenvironmental landmarks may be input by the user using an input device,such as input device 340 (FIG. 3) of user device 210, or automaticallyinput from a GPS-enabled device. The offset information may beautomatically calculated or input by the user. Offset information mayalso be obtained by identifying selected environmental landmarks on theretrieved image and automatically calculating the distance from theselected environmental landmarks to the underground facility locatemarks overlaid on the image.

In block 650, if necessary, information about the location of theunderground facility locate marks may be converted to GPS coordinates.In block 660, the retrieved aerial image and information about thelocation of the underground facility locate marks may be stored inmemory as a single combined image or electronic manifest. The electronicmanifest may be stored as, or example, a digital image or an interactiveelectronic map. Additionally or alternatively, in block 670, thegeographical coordinates of the underground facility locate marks may bestored in memory, such as memory 330 (FIG. 3), as a separate data set.The data set may be compiled as, for example, a database of GPScoordinates. In block 680, the combined image and/or separate data setmay optionally be transmitted to a central location, such as centralserver 220 (FIG. 2).

FIG. 7 is a diagram of an exemplary data set that may be stored inmemory 330 and/or transmitted to server 220. As shown in FIG. 7, a dataset 700 may include a timestamp field 710, an underground facilityidentifier field 720, an underground facility location field 730, anenvironmental landmark identifier field 740, an environmental landmarklocation field 750, an other information field 760, a marking methodfield 770, a property address field 780, and a ticket number field 790.In another implementation, the data set 700 may include additional,fewer, or different fields.

Timestamp field 710 may include time data that identifies the day and/ortime that the environmental landmark location was identified. The timedata in timestamp field 710 is shown in FIG. 7 as 9:43 a.m. on Oct. 20,2005—although any type of date and/or time code may be used. Theinformation in timestamp field 710 may be useful in establishing when alocate operation occurred.

The underground facility identifier field 720 may include an identifierthat uniquely identifies the type of underground facility that wasmarked. The identifier in underground facility identifier field 720 isshown in FIG. 7 as “power” —although any type of identifier may be used.Underground facility location field 730 may include geographic locationinformation corresponding to an underground facility locate mark. In oneimplementation, the geographic location information may include a set ofgeographic points along the marking path of the located undergroundfacility. The geographic location information in underground facilitylocation field 730 is shown in FIG. 7 as N38° 51.40748, W077° 20.27798;. . . ; N38° 51.40784, W077° 20.27865—although any type of geographiclocation information may be used. The information in undergroundfacility location field 730 may be useful in graphically presenting theunderground facility locate marks on a map, and/or to verify that thelocate operation was actually and accurately performed. Additionally, oralternatively, underground facility location field 730 may includegeographic location information for multiple underground facility locatemarks.

Environmental landmark identifier field 740 may include an identifierthat uniquely identifies the type of environmental landmark beingmarked. The identifier in environmental landmark identifier field 740 isshown in FIG. 7 as “curb” —although any type of identifier may be used.

Environmental landmark location field 750 may include geographiclocation information corresponding to the environmental landmarkidentified in environmental landmark identifier field 740. Thegeographic location information in environmental landmark location field750 is shown in FIG. 7 as N38° 51.40756, W077° 20.27805; . . . ; N38°51.40773, W077° 20.27858—although any type of geographic locationinformation may be used.

Other information field 760 may store other data that may be useful,including user notes, such as distance information that identifies adistance between one or more environmental landmarks and one or moreunderground facility locate marks. Other information field 760 is shownin FIG. 7 as including “1.2 meters between curb and power line”—although any other data may be used. Additionally and/or alternatively,other information field 760 may include audio/voice data, transcribedvoice-recognition data, or the like to incorporate user notes.

The underground facility owner field 765 may include the name of theowner/operator of the underground facility that has been marked duringthe locate operation. For example, in FIG. 7, the underground facilityowner field 765 is shown as “ABC Corp.” Because multiple undergroundfacilities may be marked during a single locate operation, it may bebeneficial to associate each marked underground facility with aparticular owner/operator.

Marking method field 770 may indicate the type of marking used at thedig area to indicate the location of an underground facility. Forexample, in FIG. 7, marking method field 770 is shown indicating redpaint. Property address field 780 may be the property address associatedwith the marking recorded in the data set 700. The property addressfield 780 may include, for example, the street address and zip code ofthe property. Other information in field 780 may include city, state,and/or county identifiers. The ticket number field 790 may include theticket number associated with the locate operation, such as ticket“1234567” shown in FIG. 7.

In one implementation, the user device 210 may store multiple data setscorresponding to multiple underground facilities identified at aparticular dig area. User device 210 may provide the data sets to server220 in a batch—such as a batch corresponding to the group of undergroundfacilities documented within the electronic manifest—or individually.The batch may be grouped together with other information generallyrelating to the locate operation, such as the name of the companyresponsible for performing the locate operation, the name of the locatetechnician, and the like. Additionally, or alternatively, the otherinformation generally relating to the locate operation may be includedin each data set.

FIG. 8 an exemplary diagram of a user interface 340 that may bepresented via the user device 210. The user interface may be presentedon a screen 800 that may be the screen of the user device 210, asdescribed herein with respect to FIG. 2. The screen 800 may display avariety of graphical elements, including but not limited to: a mapcontrol 810, an address search panel 820, a locator palette 830, anavigation palette 840, a status bar 850, a menu bar 860, a service grid870, and a scale bar 880.

Map control 810 generally may be the surface, or canvas, whereimages—such as an exemplary image 802—are displayed. The user may drawor input shapes “on top of” this surface using for example, the inputdevice 340 of FIG. 3 to identify underground facility locate marklocations. FIG. 8 shows a stylus 804 as an exemplary form of inputdevice 340.

The address search panel 820 may be used to identify imagescorresponding to a desired address. Panel 820 may, for example, accept apartial or complete address and allow the user to search for matches. Ifan excessive number of addresses match the search, then the size of theresult set may be constrained. Address search results may be displayedwhich match the address search. The listed matches may serve as aspringboard for displaying the image desired by the user. For example,when the user taps with a stylus 802 on an address match, the userdevice 210 may load the image corresponding to the selected address. Asdescribed above, this image may be stored locally on user device 210 orretrieved from central server 220.

Palettes may be generally defined as a toolbar or toolbars containingsoft buttons or other controls that are grouped in some logical order.The buttons on a palette may duplicate the commands available on themenu bar 860. The locator palette 830 may allow the user to select thetype of underground facility locate marks (e.g., electric, gas, water,sewer, telecommunications, etc.) the user will draw on the image 802.The locator palette 830 may also include a choice of various shapes orshades, such as freestyle, line, circle, rectangle, or other polygonthat the user may select to draw on the image 802. In oneimplementation, the locator palette 830 may present a list of potentialenvironmental landmark identifiers. In this case, the user may select anenvironmental landmark identifier from the list to overlay at theappropriate place on the aerial image 802.

The locator palette 830 may also include an offset tool that allows theuser to mark the distance between, for example, an environmentallandmark identifier and a drawn underground facility locate mark. Oncethe user has chosen the type of shape they wish to draw (freestyle,line, polygon, shading etc.) the application may track the user'smovements to define the layout and location of the shape. The shape maybe completed when the user terminates the drawing (for example, bylifting the stylus 804 or releasing the mouse button). A text label orother indicator may be added to the shape automatically based on thetype of underground facility locate mark or environmental landmarkselected (e.g., “electric” or “curb”) or may be manually added.

The navigation palette 840 may allow the user to zoom or pan the image802. For example, the navigation palette 840 may include selections tozoom in, zoom out, or zoom to a selected section of the image. Thenavigation palette 840 may also include pan command buttons to pan left,pan right, pan up or pan down. Other selections that may be available onthe navigation palette include buttons to alter the transparency ofeither the image 802 or the underground facility locate marks.

The status bar 850 may display information about the map control, suchas the coordinates of the subject area, the coordinates of a cursor orstylus in relation to the image 802, and the image scale. The menu bar860 may include an operating system element that allows a user to accesscommands, such as exiting the application, selecting what palettes orpanels to display, or accessing online help.

The service grid 870 is shown as an exemplary “floating” window to showhow the user interface for the screen 800 may operate in a typicaloperating system environment. The service grid 870 or any of the othergraphical elements described in relation to screen 800 may be in a fixedor floating orientation. As underground facility locate marks are drawnon the map control 810, they may appear in a list in the service grid870. Thus, the user may edit the properties of an underground facilityshape using the service grid 870, as well as by selecting the shape inthe map control 810. The service grid may include properties, such asthe type, length, circumference, and material of the marked undergroundfacility.

An electronic manifest of underground facility locate marks may serveseveral purposes. For example, the electronic manifest may providesignificant improvements in accuracy and save time for the locatetechnician. Manual sketching is time consuming and imprecise. Forexample, with manual sketching, the general geographic features of thedig area location, i.e. roads, sidewalks, landscaping, buildings, andother landmarks, must be reproduced by the locate technician. Creationof an electronic manifest that includes drafting on retrieved aerialimages may improve accuracy and eliminate drafting of these generalgeographic features.

Additionally, or alternatively, an electronic manifest of undergroundfacility locate marks may provide a variety of data formats from asingle user event. For example, electronic drafting creates data aboutthe electronic manifest which can be reviewed without viewing the image.The type of marked underground facilities can be determined based uponthe existence of different colors or other coding schema, length ofmarks for each underground facility can be approximated, and theexistence and length of offsets detected. If available, the location ofthe marks can be cross-checked to the user's description or depiction ofthe area to be marked or excavated.

Additionally, or alternatively, an electronic manifest of undergroundfacility locate marks may provide for easier dissemination andrecord-keeping. Electronic manifests can be associated with individualtickets and recalled electronically, avoiding the uncertainties anderrors associated with manual filing systems. Furthermore, electronicmanifests can be interrogated to ensure that the information recorded onthe electronic manifest accurately comports with billing data or otherinformation regarding the locate operation(s) performed.

Additionally, or alternatively, information from the electronic manifestregarding the distance between environmental landmarks and locatedunderground facility locate marks may be used to verify subsequentlocate operations or the accuracy of the electronic manifest. Forexample, if the information identifies an underground facility asrunning parallel to the curb at a distance of three meters, thatinformation may be used to assess the accuracy or consistency of asubsequent locate operation at the same dig area or, upon inspection,the accuracy of the electronic manifest.

Additionally, or alternatively, information from the electronic manifestregarding the number and types of underground facilities may be used toestimate the scope of a subsequent locate operation to be performed at adig area. For example, a large number of underground facilities may beindicative of an extensive (i.e., time-consuming) locate operation.

Additionally, or alternatively, information from the electronic manifestmay be used by a quality control supervisor and/or damage inspector toverify the accuracy of the underground facility locate marks. Forexample, if the user who performed a locate operation indicated that anunderground facility runs parallel to a driveway at a distance of twometers, then the quality control supervisor or damage inspector may usethis information to verify whether the marks properly reflected theactual location of the underground facilities present within the digarea. Also information from the electronic manifest may be used to traina user and/or to perform quality control relating to a user's work.

CONCLUSION

Aspects of the invention as described herein enable retrieving from adatabase the appropriate aerial image of a specific geographic location,or dig area, where locate operations are to be conducted for undergroundfacilities. The user may draft, on the retrieved image, a variety offeatures, including but not limited to (1) the type of undergroundfacilities marked using an appropriate color or other coding schema, (2)the number of underground facilities marked within the dig area, (3) theapproximate geographic location of each set of underground facilitylocate marks, and (4) the appropriate environmental landmark offsets foreach set of underground facility locate marks. The combination of theretrieved image and additional information drafted by the user may besaved in a variety of formats as an electronic manifest. Otherinformation regarding the specific geographic location of the locatemarks and environmental landmarks may be incorporated into theelectronic manifest using direct input from GPS-enabled positioningtools and the like.

The foregoing description is not intended to be exhaustive or to limitthe description to the precise form disclosed. Modifications andvariations are possible in light of the above disclosure or may beacquired from practice of the invention.

For example, certain information was described as being presentedvisually on a screen of user device 210. In other implementations, thisinformation may be audibly provided to the user. Also, particularinformation was described as being input via an input device 340, suchas a screen of user device 210. In other implementations, thisinformation may be provided in other ways, such as by receiving inputsvia input keys and/or buttons, by recognizing speech of the user, or bymonitoring a condition of the user. More particularly, the input device340 may be capable of capturing signals that reflect a user's intent.For example, the input device 340 may include a microphone that cancapture a user's intent by capturing the user's audible commands.Alternatively, the input device 340 may interact with a device thatmonitors a condition of the user, such as eye movement, brain activity,or heart rate.

As another example, certain components, such as user device 210 andcentral server 220 were described as using an image cache. In otherimplementations, user device 210 and/or central server 220 maycommunicate with an image server (such as imager server 230) inreal-time, so that no image cache may be required. In still otherimplementations, the user device 210 may, for example, communicate inreal time with the central server 220.

As another example, it should be noted that reference to a GPS-enableddevice is not limited to GPS systems only, and that any globalnavigation satellite system or other system that provides geo-spatialpositioning may be used in implementations of the invention.

Also, while a series of blocks has been described with regard to FIG. 6,the order of the blocks may be modified in other implementations.Further, non-dependent blocks may be performed in parallel.

It will be apparent that aspects, as described above, may be implementedin many different forms of software, firmware, and hardware in theimplementations illustrated in the figures. The actual software code orspecialized control hardware used to implement these aspects is notlimiting of the description provided herein. Thus, the operation andbehavior of the aspects were described without reference to the specificsoftware code—it being understood that software and control hardware canbe designed to implement the aspects based on the description herein.

Even though particular combinations of features are recited in theclaims and/or disclosed in the specification, these combinations are notintended to limit the invention. In fact, many of these features may becombined in ways not specifically recited in the claims and/or disclosedin the specification.

No element, act, or instruction used in the present application shouldbe construed as critical or essential to the invention unless explicitlydescribed as such. Also, as used herein, the article “a” is intended toinclude one or more items. Where only one item is intended, the term“one” or similar language is used. Further, the phrase “based on” isintended to mean “based, at least in part, on” unless explicitly statedotherwise.

What is claimed is:
 1. A method performed by a device, the methodcomprising: receiving first information regarding a particulargeographic area including a dig area; retrieving an aerial image of theparticular geographic area including the dig area; displaying the aerialimage; overlaying, on the displayed aerial image, second informationconcerning an approximate geographic location of a locate mark placed ona surface above an underground facility detected by a locate technicianperforming a locate operation in the dig area, the locate mark includingat least one of a) paint, b) at least one flag, and c) at least onecolored marker, denoting a presence of the underground facility; andstoring the aerial image and the second information concerning theapproximate geographic location of the locate mark denoting theunderground facility.
 2. The method of claim 1, wherein the firstinformation includes a geographic address of the particular geographicarea.
 3. The method of claim 1, further comprising receiving user inputthat identifies the approximate geographic location of the locate markdenoting the underground facility within the geographic area; andoverlaying, on the displayed aerial image, the second information basedon the user input.
 4. The method of claim 3, where receiving the userinput that identifies the approximate geographic location of the locatemark denoting the underground facility within the geographic areaincludes receiving the user input from an input device.
 5. The method ofclaim 3, where receiving the user input that identifies the geographiclocation of the locate mark denoting the underground facility within thegeographic area includes receiving data from a global positioning system(GPS)-enabled device.
 6. The method of claim 1, further comprising:determining a distance from an environmental landmark in the displayedaerial image to the locate mark denoting the underground facility; anddisplaying the distance from the environmental landmark to the locatemark denoting the underground facility on the displayed aerial image. 7.The method of claim 1, further comprising: converting the secondinformation concerning the approximate geographic location of the locatemark denoting the underground facility to a data set of globalpositioning system (GPS) coordinates.
 8. The method of claim 1, whereoverlaying, on the displayed aerial image, the second informationconcerning the approximate geographic location of the locate markdenoting the underground facility includes: permitting a user to draw ashape on the displayed aerial image; and indicating global coordinatescorresponding to the drawn shape.
 9. The method of claim 1, whereoverlaying, on the displayed aerial image, the second informationconcerning the approximate geographic location of the locate markdenoting the underground facility includes: receiving locationinformation from a global positioning system (GPS)-enabled device; andpresenting the location information from the GPS-enabled device on thedisplayed aerial image.
 10. The method of claim 9, where the GPS-enableddevice is a locating device or a marking device.
 11. The method of claim1, further comprising: overlaying third information on the displayedaerial image indicating a type of the underground facility denoted bythe locate mark.
 12. The method of claim 1, further comprising:receiving, from a global positioning system (GPS)-enabled device,location information that identifies the approximate geographic locationof the locate mark denoting the underground facility within thegeographic area; and overlaying, on the displayed aerial image, thesecond information based on the location information.
 13. The method ofclaim 1, where overlaying, on the displayed aerial image, the secondinformation concerning the geographic location of the locate markdenoting the underground facility includes: providing a graphicalobject, corresponding to a type of underground facility, on thedisplayed aerial image to show the approximate geographic location ofthe locate mark denoting the underground facility on the displayedaerial image.
 14. The method of claim 1, further comprising:transmitting the aerial image and the second information concerning theapproximate geographic location of the of the locate mark denoting anunderground facility as a single image file.
 15. A device, comprising: amemory to store aerial images of a plurality of geographic areas; and aprocessing unit to: receive first information regarding a particular oneof the geographic areas including a dig area, retrieve one of the aerialimages from the memory based on the received first information, receivesecond information concerning an approximate geographic location of anunderground facility locate mark including at least one of a) paint, b)at least one flag, and c) at least one colored marker, placed on asurface above an underground facility detected by a locate technicianperforming a locate operation in the dig area and located within theparticular one of the geographic areas including the dig area, present,on the retrieved aerial image, the second information concerning theapproximate geographic location of the underground facility locate mark,and store, in the memory, the retrieved aerial image and the secondinformation concerning the approximate geographic location of theunderground facility locate mark.
 16. The device of claim 15, where theprocessing unit is further configured to associate a geographic addresswith the retrieved aerial image of the particular geographic area. 17.The device of claim 15, where the processing unit is further configuredto convert the second information concerning the approximate geographiclocation of the underground facility locate mark to a data set of globalpositioning system (GPS) coordinates.
 18. The device of claim 15, wherethe processing unit is further configured to: permit a user to drawshapes on the retrieved aerial image; and indicate global coordinatescorresponding to the drawn shapes.
 19. The device of claim 15, where theprocessing unit is further configured to: receive the second informationas location information from a global positioning system (GPS)-enableddevice; and display the location information from the GPS-enabled deviceon the retrieved aerial image.
 20. The device of claim 15, where theprocessing unit is further configured to: receive input from a user thatidentifies a type of the underground facility denoted by the locatemark; and present third information on the retrieved aerial imageconcerning the type of the underground facility locate marks.
 21. Thedevice of claim 15, further comprising: a communication interface, wherethe processing unit is further configured to transmit to a serverthrough the communication interface the retrieved aerial image and thesecond information concerning the approximate geographic location of theunderground facility locate mark.
 22. A system, comprising: a centralserver to store a plurality of aerial images of a correspondingplurality of geographical locations; and a user device to: identify aparticular geographic location including a dig area, determine whetherthe user device stores an aerial image corresponding to the particulargeographic location including the dig area, retrieve the aerial imagefrom the central server when the user device does not store the aerialimage corresponding to the particular geographic location, retrieve theaerial image from a local memory when the user device stores the aerialimage corresponding to the particular geographic location, display theaerial image, receive information regarding an approximate location ofunderground facility locate marks including at least one of a) paint, b)at least one flag, and c) at least one colored marker, located at theparticular geographic location above an underground facility detected bya locate technician performing a locate operation, and present, on thedisplayed aerial image, a marking that identifies the approximatelocation of the underground facility locate marks.
 23. A methodperformed by a device, comprising: receiving first information regardinga particular geographic area including a dig area; retrieving an aerialimage of the particular geographic area including the dig area;receiving, from a global positioning system (GPS)-enabled device, secondinformation regarding an approximate location of underground facilitylocate marks including at least one of a) paint, b) at least one flag,and c) at least one colored marker, on a surface above one or moreunderground facilities detected by a locate technician performing alocate operation; displaying, as a combined image, the aerial image andthe second information regarding the approximate location of undergroundfacility locate marks; and storing the combined image.